Cutting inserts were traditionally held to rigid insert seats with a clamp. A clamp according to the specification and claims meaning a member having a head and a shank of either a threaded type, e.g. a screw, or a non-threaded type, e.g. a pin. An example of a clamp with a non-threaded shank is disclosed in U.S. Pat. No. 9,033,621, assigned to the present applicant.
It was discovered that, particularly for parting-off, an improved design without the need for a clamp was feasible (e.g. the assembly disclosed in U.S. Pat. No. 7,326,007, assigned to the present applicant). In such design, instead of utilizing a clamp, a single-cutting-edged solid insert (“single-cutting-edged” or stated differently “non-indexable”; “solid” or stated differently “devoid of a clamping hole”) is resiliently retained to a seat of tool by elasticity of opposing portions of the insert seat. A notable advantage of such clamp-less design is the relatively narrow machining width enabled, since the insert and the tool widths do not need to accommodate a clamp.
Yet a further design utilizing a single-cutting-edged solid insert, but with a dual resilient insert seat and clamp (called a “threaded fastener” therein), is shown in U.S. Pat. No. 7,578,640, also assigned to the present applicant. On the one hand, the construction is more complicated due to the presence of the additional component, i.e. the clamp, on the other since the resilient seat also clamps the insert a relatively narrow clamp can be utilized, thereby retaining at least some of the relatively narrow machining width benefit.